On topic, I'd say that it is too early to know exactly what KG's ceiling will be once his legs are fully back under him. I will say, though, that it appears to me that he is using the early part of the season as an extended pre-season. He seems to be working on his timing, working on his jumper, and working on his wind. When he does expend extra energy it's on defense, as I haven't really seen him try to force the offense yet.
As for the Rondo alley-oops, I would think now would be the perfect time for them to work the kinks out. Especially in games that are blowouts. As Roy has pointed out in the past, several of the misses have been KG back-rimming them (timing issue) not under-rimming them like earlier in the preseason.